TB 9-6625-2215-24
f. Set INT STD-EXT STD switch on rear panel of frequency counter to EXT STD.
21. Time Base Stability
NOTE
Some models do not have an internal oscillator.
When
calibrating these models, omit this check.
a. Performance Check
(1) Connect frequency counter A input to TI OSC jack (rear panel).
(2) Adjust Y1 ADJ (fig. 1) as required to obtain frequency counter indication of exact
frequency stamped on TCXO CASE (fig. 1).
(3) Adjust autotransformer output from 105 to 125 V while monitoring frequency
counter indication. Frequency will not change by more than 0.5 Hz.
(4) Adjust autotransformer output for 115 V.
Figure 1. Test Instrument - (HP 5303B) - Bottom View.
b. Adjustments. No further adjustments can be made.